Concealed loud speaker for radio receiving sets



De.l27,1927. 1,653,795

J. wou-'F CONCEALED LOUD SPEAKER FOR RADIO RECEIVING SETS Filed April llf2. 1924 2 Sheets-,Sheet l Fina. l

zz-y M 25a 23 I3 20 23 49 45 44 14 mvyoxz Mgg-4% Dec. 27, 1927.

.l. woLFF CONCEALED LOUD SPEAKER FOR RADIQ RECEIVING` SETS 2 {Sheets- Sheet 2 Filed. April 12, 1924 FIG. A

Patented Dec. 27, 1927.

UNITED STATES g 1,653,195 PATENT OFFICE.

JOSEPH WOLFF, OF BROOKLYN, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, TO SONORA PHONOGRAPH COMPANY, IN C., A CORPORATION OF NEW YORK.

CONCEALED LOUD SPEAKER FOR RADIO RECEIVING SETS.

Application led April 12, 1924. Serial No. 705,980.

rlhis invention relates generally to a loud speaker for radio receiving sets, and more particulaily toa concealed loud speaker.

One of the objects of this` invention is to provide a supplemental cabinet unit having a sound amplifying member with a sound passage therethrough, said cabinet unit being adapted for, and capable of, being associated with any of the well-known receivio ing sets now on the market. The loud speakers now in use generally employ a horn separate and apart from the radio receiving set, which is large, unsightly, and frequently takes up so much room that it is in the way; I have, therefore, constructed a cabinet which may be` employed as a supplemental cabinet to a radio receiving set or which may be aiiiXed to the radio receiving set in a separate compartment and thus conceal the horn. The concealed horn, whether combined with the radio receiving set or in a supplemental cabinet, tends to econ'omize Space and at the same time provide means for greatly improving the reproduction and amplification of the sound. i

Another object of the invention is to provide an improved loud speaker in cabinet form, which will be compact, simple in construction, economical to manufacture eiiicient in operation, and attractive in appearance. i v

Another object of the invention is to provide aloud speaker horn compact in form, efficient in operation and adapted for use in a cabinet.

A further object is to provide a cabinet and a separate'horn to be placed therein and to cooperate therewith to give improved loud speaker effects substantially Jfree fromy distortion. t

A further object oi' the invention is to pro.- vide means of the character herein described, simple in construction, thoroughly reliable and eilicient in its purpose, positive in operation, and inexpensive to manufacture.

With these and other objects in view to be more fully setforth hereinafter, the invention consistsin the novel construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter described in the specication and illustrated in the accompanying drawings considered together or separately.

The inventive idea involved is capable of receiving a variety of mechanical expresmiA sions, one oi which for the purpose of illustrating the invention, is shown in the accompanying drawings.

The invention will be first described in connection with the accompanying drawings `illustrating one embodiment of my invening set.

ln. the illustrated embodiment of the invention, the loud speaker 10 comprises a horn 11 and acabinet 12 therefor which comprises a base 13 provided with feet 14 adjacent the four. corners thereof. The cabinet' 12 also comprises lett and right side walls 15 and 16 respectively, a rear wall 17, and a top 18. To protect the horn and to give anv attractive appearance to the iront of the cabinet, provision may be made for a reinovable grille 19, which iits between the side walls 15 and 16, and to hold the grille in position, provision may be made for a shallow groove 20 in the base and for a groove 21 in the top 18 of .the cabinet. The upper edge of the grille may be insertedin the groove 21 and its lower edge swung rearwardly into position to allow it to be lowered into the groove 20, the upper edge of the grille then assuming the position indicated by the dotted line 22 atthe top of Fig. 2.

The loud speaker horn 11 has a mouth .substantially co-extensive with the opening at the iront of the cabinet 12 and has a hori- Zontal lower wall 23 extending substantially to the rear of the cabinet, said wall having supports 23a-23a which hold it in a suspeidedposition from the outer casing. Such suspension of the loudspeaker horn 11 will improvethe reproduction and amplilication and make the speaker substantially free from distortion. The left and right walls 24 and 25 respectively converge rearwardly, the left elevation, part wall 24 terminating at a point 23 and the right wall 25 being curved gradually to the left (Fig. 2) to a point 27. As shown in Fig. 3, the upper wall, 27 ot the horn is brought downwardly rather abruptly troni its trent edge and given ia gradual curve rearwardly to a substantially horizontal direction at the point 28.

At the points 26, 27 and 23 the walls 24, 25 and 27 merge into the sides ol a pasft je 29 in a block 30, the passage 29 being' curi ld gradually to a vertical direction at the top ci the block 30 where itcominunicates with a passage 3l in anextension 32 which corresponds to the tone arm ot a phonograph. The extension 32, which may be connected with the block 30 by any suitable means such as screws 33, gradually decreases in size and has attached thereto a phone-attachment 34 which may be of the well known Balduin type. The attachment 34 has a diaphragm 35 and a head 36 provided with an opening 37 opposite the center of the diaphragm 35, and with a sleeve 33 lor attachment to the end ot the extension 32 by suitable means such as a set screw 39. f

To connect the loud speaker l0 with a radio receiving set 40. (Fig. 4), provision is made ott two conductors 4l and 42 connected with the attacliment34 at 43 and having an insuiating covering 44 extending along the greater part of the length thcreo'l'. Freien ably, provision isy made for an opening 45 in the base 13 ot the casing and the conductors 41 and 42 with their-,casing 44 `ci:- tend downwardly from the attachment 34, through such opening, and away from the cabinet for connection with the radio receiving set. For such connection the conductors 4l and 42 are provided with plugs 46 and 47k respectively to fit into suitable sockets (not shown) in the receiving set 40. .s

As indicated in Figs. l, 2 and 3, the horn l1 is supported on the base oli the cabinet l2 by means of teet 23n `at the front, and a `toot 49 at the rear, the feet 23n and 49 being ol suitable material such, for example, as telt or rubber. It will also be seen that the horn 11 is spaced from the cabinet at all points.` It has been found that, with a horn ot the torni described and positioned in the cabinet as indicated, exceptionally good and improved results will be obtained, and distortion prevented.

In the embodiment of the invention illustrated, the cabinet and the horn, with the exception of the metal tone arin 32, are made of wood, but I wish it distinctly understood that my invention not to be so limited.

It will be obvious from the foregoing that I have invented a very unique and novel concealed horn radio loud speaker in which the loud speaker is concealed within the casing and suspended therein, said4 loud speaker being supported on the base and in' no inanner being in contact with the walls ol" the casing. l i'ind that a device so constructed produces exceptional and iniproved sound reproduction, 'tree ironiA` distortion. l

ln accordaijice with the provisions ot' the patent statute, l have described the principle oit iny invention, together with the apparatus which I now consider to represent the best embodiment thereo'l", but I desire it understood that my invention is not confined to the particular torni ot apparatus herein shown and described, the saine being merely illustrative, and that thc invention canbe carried'out in other ways without departing from the spirit of niy invention, and, therel'ore, l claim broadly tlieright to employ all equivalent iiistrunientalities coming within thc scope ot the appended claims, and by nieans Vol which objects of my inventionare attained, and the new results accomplished, as herein set torth, as it is obvious that the particular' embodiment herein shown and described is only one of many that can be employed to attain these objects and accomplish these results.

Having now described my invention, what I claim and desire-to secure by Letter! Patent is: f

l. In a device of the character stated, a sound ainplilier including a rear inlet `portion extending horizontally andthence downwardly, said inlet anddow'nwardly extending portion being of gradually increasing area in cross section, a front Iexit portion extending -lorwardly trom said horizontal rear inlet portion at substantially an angle thereto and having a rear vertical side Wall against which said downwardly extending inlet portion discharges, outwardly diverging vertical walls and an upwardly diverging top wall for said exit portion through which the reproduced sounds' are discharged, and means for securing said rear `inlet and iront exit aniplilier portions in assembled position.

2. In an acoustic device, a sound amplifier having a rear amplilier part extending horizontally and'thcnce downwardly, saidpart beingci gradually increasing area in cross section, a liront amplifier part extending forwardly:troni said rear aniplilier 'part at substantially a right angle to said horizontal' rear vaniplilier part and having a rear side wall against which said downwardly extending amplilier part discharges, and outwardly diverging vertical side and top walls through which the reproduced soundsare discl'iarged, said rear horizontal inlet part being oit a length not excceding'the front ainpliii'er partY of said amplifier yand bein':

in proximity to the rear outer surface Orl said aniplitier. A

3. In a device ot the character stated, a sound a-nipliier having a rear amplifier" part which part is of gradually increasing area in lll) cross-section, a front ampliier part Apositioned at right angles to said rear ampliier part the latter being disposed horizontally above the rear Walls of the front amplifier part, the Walls or' which are converging and extend donf'nxvardly and thence inwardly towards the side Wall ot the rear portion of the base of said front ainpler part against which the sound Waves iinpinge upon enter* ing said iront ainpliier part, and outwardly diverging` side and top Walls for said front amplifier part.

4. In a device of the character stated7 a sound amplifier having a rear portion having an inlet end and an enlarged exit end, the 15 said inlet end merging into a laterally extending branch, the latter merging into a downwardly and inwardly extending branch, a liront exit amplifier portion located beloviT the lateral branch of said ampliier portion 20 and having its inlet end connected with the venlarged exit end of said rear portion.

This specification signed this 10th day of April7 1924.

JOSEPH WOLFF. 

